(1) Field of Invention
The present invention relates to a series of novel silicone phospholipid polymers which are highly lubricious, produce high levels of copious foam, have low irritation properties and are film formers when applied to hair and skin. The compounds, because they are based upon terminal dimethicone copoylols make flat polymers when phosphated and derivatized. As will become apparent, the polymers of the present invention will orientate themselves into planar sheets, silicone on one side of the plane, fatty portion on the other side in aqueous and other solutions. These flat polymers have the unexpected property of producing non-occlusive films when applied to hair skin and fiber. They contain a pendant ionizable phosphate group and a quaternary amine compound are amphoterics that is they contain both a positive and negative charge in the same molecule. They resemble polymers of naturally occurring phospholipids and tend to form bilayer sheets rather than micelles when used in making oil in water emulsions. Since the compounds of the present invention are high molecular weight silicone polymers, they have a high degree of oxidative stability, even at elevated temperatures and are nonirritating to skin and eyes. In addition, these compounds are non volatile and exhibit a inverse cloud point. These combination of properties makes these polymers ideally suited for use in personal care applications.
The technology used to produce the polymeric phospholipids of the present invention is very flexible and allows us to prepare performance tailored molecules for specific applications. As will become obvious, these materials unlike phosphobetaines, form lipid bilayers in aqueous solution and consequently are called phospholipids rather than phosphobetaines. This property is based upon the specific polymeric structure as will become apparent.
(2) Description of the Arts and Practices
Silicone oils (dimethylpolysiloxane) have been known to be active at the surface of plastic, cellulosic and synthetic fibers as well as paper. Despite the fact that they are lubricants that are stable to oxidation, their high cost and lack of durability has made them cost prohibitive in most application areas. Silicone oils need to be emulsified prior to application. This requires high pressure equipment, surface active agents and generally results in a milky emulsion. Emulsions have experienced stability problems both in terms of freeze thaw instability and upon heating. This has resulted in minimal acceptance of them in commericial products.
The low efficiency of silicone oils is due to the fact that the oil is very water insoluble. Emulsions are generally prepared which contain silicone dispersed in micelles. While this method of application is easier for processing, much of the oil stays in the surfactant micelle and never gets deposited on the fiber. That which does deposit on the fiber surface remains there by hydrophobic binding, not ionic bonding. Since the polydimethylsiloxane is not ionically bonded the effect is very transient. The product is removed with one washing.
Fatty Phosphobetaines have been known since 1974. There are several patents which have issued on this topic.
U.S. Pat. Nos. 3,856,893 and 3,928,509 both issued to Diery disclose the basic technology used to make phosphobetaines and the alkyl derivatives.
Later, phosphobetaines based upon alkylamidoamines and imidazolines rather than alkyl amines were patented in U.S. Pat. No. 4,209,449 issued in 1980 to Mayhew and O'Lenick. This patent teaches that phosphate quats can be prepared by the reaction of a phosphate salt, three equivalents of epichlorohydrin and in a subsequent step, three equivalents of a tertiary amine.
U.S. Pat. No. 4,215,064 issued in 1980 to Lindemann et al teaches the basic technology that is used for the preparation of amido and imidazoline based phosphobetaines. These compounds can be prepared by the reaction of a phosphate salt, one equivalent of epichlorohydrin and one equivalent of a tertiary amine.
U.S. Pat. No. 4,243,602 issued in 1981 to O'Lenick and Mayhew teaches the basic technology that is used for the preparation of phosphobetaines based upon phosphorous acid salts. These compounds can be prepared by the reaction of a phosphorous acid salt, one equivalent of epichlorohydrin and one equivalent of a tertiary amine.
U.S. Pat. No. 4,261,911 issued in 1981 to Lindemann et al teaches the utilization of phosphobetaines based upon phosphorous acid. These compounds are useful as surfactants.
U.S. Pat. No. 4,283,542 issued in 1981 to O'Lenick and Mayhew teaches the process technology used for the preparation of phosphobetaines. These compounds can be prepared by the reaction of a phosphate salt, one equivalent of epichlorohydrin and one equivalent of a tertiary amine.
U.S. Pat. No. 4,336,386 issued in 1982 to O'Lenick and Mayhew teaches the technology for the preparation of imidazoline derived phosphobetaines based upon phosphorous acid salts. These compounds can be prepared by the reaction of a phosphorous acid salt, one equivalent of epichlorohydrin and one equivalent of an imidazoline.
U.S. Pat. No. 4,503,002 which is related to U.S. Pat. No. 4,209,449 issued in 1985 to Mayhew and O'Lenick teach that phosphate quats can be prepared by the reaction of a phosphate salt, three equivalents of epichlorohydrin and three equivalents of a tertiary amine.
U.S. Pat. No. 5,070,171 issued to O'Lenick teaches that silicone phosphate esters can be prepared by phosphating internal (i.e. non-terminal) dimethicone copolyols. U.S. Pat. No. 5,091,493 issued to O'Lenick teaches that non-polymeric silicone phosphobetaines can be prepared using the phosphate esters of U.S. Pat. No. 5,070,171.
U.S. Pat. No. 5,149,765 to O'Lenick teaches that terminal dimethicone copolyols can be used to produce phosphates. These materials are the starting raw materials for preparation of the compounds of the present invention.
Despite the fact that there was significant patenting of phosphobetaine compounds based upon phosphoric acid salts, phosphorous acids salts, tertiary amines and imidazolines, and more recently silicone based phosphobetaines, the technology needed to make polymeric compounds was not available until the it was discovered that the terminal dimethicone copolyols could be used as starting materials for the preparation of polymeric silicone phospholipids. Terminal silicone phosphates are the basic raw material used for the preparation of polymeric silicone based phosphobetaines. This is due to the fact that the nature of these materials results in an unexpected film forming polymer which is non-occlusive and non-irritating. This suggests the use of these materials in barrier creams to protect the scalp from irritating processes like hair permanent waves and the relaxing of curly hair. The exact nature of the polymeric structure will become apparent.